Thin-walled container

ABSTRACT

There is described a thin-walled metal container for storing and serving food and having a receptacle portion provided, at its rim, with a continuous flange including two opposed, longitudinally straight zones and a lid portion provided with an edge zone crimped about said flange. At two opposed ends of the container, adjacent said straight zones, each crimp zone continues in a pull tab which, when actuated, disengages the last-named crimp zones, while the said longitudinally straight zones of the receptacle flange serve as guide rails for the lid portion when the latter is slid off the receptacle portion.

United States Patent 1191 Wagner et al.

[ Dec. 17, 1974 THIN-WALLED CONTAINER [75] Inventors: Ulrich Wagner, Esslingen; Eugen Scherr, Ebersbach; Karl-Dieter Fuchslocher, Esslingen, all of [21] Appl. No.: 278,380

[30] Foreign Application Priority Data Aug. 6, 1971 Germany 2139588 [56] References Cited UNITED STATES PATENTS Fisher 99/17] H X 2,903,173 9/1959 Hopkins 229/43 X 2,944,726 7/1960 McCauley.... 229/44 CB 3,153,505 10/1964 Bessett 229/43 Primary Examiner-William 1. Price Assistant Examiner-Stephen P. Garbe Attorney, Agent, or FirmEdwin E. Greigg [5 7] ABSTRACT There is described a thin-walled metal container for storing and serving food and having a receptacle portion provided, at its rim, with a continuous flange including two opposed, longitudinally straight zones and a lid portion provided with an edge zone crimped about said flange. At two opposed ends of the container, adjacent said straight zones, each crimp zone continues in a pull tab which, when actuated, disengages the last-named crimp zones, while the said longitudinally straight zones of the receptacle flange serve as guide rails for the lid portion when the latter is slid off the receptacle portion.

9 Claims, 8 Drawing Figures PATENTEL 3K3] 3,854, 6453 saw 1 OF 4 PATEHTEL SEC I 71974 SHEET 2 0F 4 PATENIEL MI I 7 I974 saw u HF a Fig. 8

1 THIN-WALLED CONTAINER BACKGROUND OF THE INVENTION This invention relates to a thin-walled container for prepared food or the like and is of the type which has a lower or receptacle portion (hereinafter referred to as receptacle) preferably made of aluminum and a one-piece upper or lid portion (hereinafter designated as lid) which serves as a closure for the receptacle and which is made of very thin aluminum or comparable metal. The edge of the lid is at all sides crimped about a continuous receptacle flange having one pair of parallel extending longitudinally straight first flange ranges which are joined by second flange ranges of the receptacle flange that extend through the rounded flange comer zones from one such zone to the other.

Containers of the aforenoted type are used in particular for storing deep-frozen prepared food; they usually constitute the serving dish subsequent to the removal of the lid. These containers are mass-produced inexpensive articles which may be found particularly in snack bars or the like. The containers, for economic reasons, are made of as thin a wall as possible. In order to ensure that the receptacle is sufficiently rigid, it is usually provided at its rim with a continuous flange which expediently has a rolled-in edge preferably bent obliquely downwardly and outwardly. The lid has a wall thickness which is even smaller than that of the receptacle, since it merely has the function to cover the receptacle during shipment and storage. In the snack bar or other place of utilization, the container, together with the food disposed therein, is usually heated in a hot air oven or the like until the food reaches the desired temperature. During this treatment, the container remains closed and is opened only by the consumer at his table. In case of hot containers such an opening operation is not without certain difficulties. A convenient known way of opening such containers resides in completely tearing through the lid by means of a pull tab secured thereto and the remaining two lateral portions are removed sideways by hand. The torn-off middle portion rolls up in a coil-like manner. If at its underside gravy or the like adhered, such material may drip, squirt or spill on the user. Although such an occurrence may be largely prevented if, in case of a sufficiently wide pull tab, the mid portion is bent inwardly in the middle during tearing. The possibility, however, of not performing such bending step is not excluded. It would furthermore be advantageous and desirable to be able to remove the lid in its entirety in order to facilitate its final disposal by the cleaning personnel. I

OBJECT, SUMMARY AND ADVANTAGES OF TI-I INVENTION It is an object of the invention to provide an improved container of the aforenoted type in which the lid thereof is formed in such a manner that it may be removed in its entirety in a simple manner even by persons without any experience in such operation without the danger of spilling gravy or other food material adhering to the underside of the lid. It is also an object of the invention to so design the container lid that it may be removed without difficulty even if the container is hot. It is also an object of the invention to provide a container of the aforenoted type which has a lid of simple structure that is inexpensive to manufacture; this is of prime importance in making mass-produced articles of this type.

Briefly stated, according to the invention, in a con- 5 tainer of the aforenoted type, the lid is provided, at those sides which lie on second flange zones, with pull tabs which are integral continuations of the associated crimp zones and have base zones below the bent corner ranges of the receptacle flange. The second flange zones are opposed to one another and are located adjacent the first flange zones. By means of the pull tabs the crimps of the lid, with exception of the crimps situated at the aforenoted two first flange ranges, may be loosened to such an extent that the lid may be removed in its entirety by sliding it, with the application of a very small force, along the remaining crimped zones which are constituted by the first flange ranges and which serve as guide rails.

The container according to the invention may be opened with ease without the danger of spilling or squirting its contents. Also, it may be opened without any difficulty even in a hot condition, since the pull tabs have a lower temperature than the remainder of the container. The opening of the crimp may be effected exclusively by means of the pull tabs, so that, as a rule, no other container portions have to be touched by hand. In case the container is full, the sliding of the lid on the first flange ranges for the purpose of its removal may be effected by pulling on one of the two pull tabs or, if desired, by simultaneously pulling on both tabs. If it is desired to immobilize the receptacle during this operation, there is required only a very slight force and therefore the receptacle may be held stationary by exerting a light pressure on an exposed flange range. In most cases such containers are disposed, during opening, in a depression of a tray. In such a case, even under unfavorable circumstances an immobilization of the re ceptacle by hand during the sliding motion of the lid is not necessary. Since, according to the invention, the removed lid is not torn into several parts, it may be disposed in a very simple manner or it may serve as a tray beneath the container portion. After the food has been consumed, it may be collected for disposal together with the receptacle with one manual operation.

All the aforenoted advantages may be achieved practically without additional cost. The consumption of material for providing the grip tabs is extremely small and thus, as far as costs are concerned, practically does not have to be considered. In other details the lid may correspond to lid structures of known type.

The invention will be better understood as well as further objects and advantages become more apparent from the ensuing detailed specification of a preferred,

with the drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a partially broken-away top plan view of the preferred embodiment;

FIG. 2 is a sectional view along line AB of FIG. 1;

FIG. 3 is a fragmentary sectional view along line C-D of FIG. 1;

FIG. 4 is a plan view of a planar blank of the lid forming part of the container illustrated in FIG. 1;

FIG. 5 is a fragmentary sectional view along line E-F of FIG 4;

although exemplary embodiment, taken in conjunction FIG. 6 is a modification of the structure shown in FIG. 3.

FIG. 7 is a view similar to FIG. 4 illustrating an alternate embodiment of the pull tabs; and

FIG. 8 is a view similar to FIG. 1 illustrating an alternate embodiment of the pull tabs.

DESCRIPTION OF THE PREFERRED EMBODIMENT Turning now to FIGS. 1 3, the container shown therein comprises a receptacle 10 and a lid 11 which serves for covering the receptacle opening. Both components 10 and 11 are made of thin aluminum foils; the lid 11 has a wall thickness that is less than that of the receptacle 10 and is approximately 0.03 0.08, preferably 0.04 0.05 mm.

The receptacle 10 which is shaped as a serving dish, has, in the illustrated preferred embodiment, a continuous horizontal, outwardly directed flange 12, having a rolled-in edge 13 for the purpose of reinforcement and better support. The flange 12 has a substantially rectangular outline, wherein the straight flange ranges 15, 16, 17 and 18 are connected to one another by rounded corner zones 14, whose radius of curvature is approximately 1.5 2.5 cm. The long straight flange zones 16, 18 form first flange zones, while the short flange zones 15, 17 form the second flange zones.

The flange 12 of the receptacle 10 may have an outline and orientation different from those shown in FIGS. 1 and 2. Advantageously, it may be bent slightly angularly downwardly at an angle of about 10 25 with respect'to the opening plane of the receptacle 10 (FIG. 6). The receptacle 10 is of known structure.

The edge of the lid 11 is crimped downwardly and inwardly about the flange 12 along its entire circumference. In FIG. 4 the bottom crimp range of the lid edge is illustrated at 19 in the blank. The two short sides 20, 21 of the crimp range 19 of the lid 11 continue in integral grip tabs 22, 23, respectively, the theoretical base lines of which are indicated in dash dotted lines at 24 in FIG. 4. In the embodiment shown, each crimp range in the second flange zone or 17 is provided with a sole, relatively wide pull tab. Instead of such sole pull tab two or more pull tabs may be provided that are disposed side-by-side and separated from one another by means of a slit or a triangular cutout. FIG. 7 shows a configuration wherein pull tabs 22a, 22b, 23a and 23b are shown. It is also feasible to provide separate pull tabs for each comer zone; these last-named pull tabs would then serve only for the disengagement of the crimp in the corner zones. As the lid 11 is crimped about the flange 12 of the receptacle 10, the base lines 24 of the grip tabs will become crease lines of the lid 11, where the crimp range 19 of the lid 11, lying against the underside of the flange 12 terminates and continues as the pull tab 22 or 23. Thus, the grip tabs begin at the base lines 24 which terminate at locations 26. The latter are situated approximately in the middle of each rounded corner zone. The base line 24 of each pull tab does not have to extend as far as the mid point of the rounded corner zones. It may, however, extend even therebeyond, for example as shown in FIG. 8, or as far as the beginning of the first flange zones l6, 18. The pull tabs 22, 23 are folded over the upper side of the lid 11 as illustrated in FIGS. 1 and 2.

It has been found that in general it is suflicient if the pull tab zones associated with the corner zones extend entirely or substantially only beneath the corner zone of the crimp. Thus, when the pull tab is folded over the top of the lid 11, it covers entirely or substantially only the second flange zone 15 or 17. In some instances it may be expedient, however, to provide that the upwardly and backwardly folded pull tab also covers the corner zones.

As it is particularly well seen in FIG. 4, in the crimp zone 19 there are provided four slits 27, one situated at each terminus of the straight first flange ranges l6 and 18 of the receptacle 10. With each pair of oppositely disposed, aligned slits 27 there is associated a pre-' formed crease line 29 (also shown in FIG. 5) which extends from one slit to the other. The aforenoted slits 27 and crease lines 29 facilitate the removal of the lid 11 from the receptacle l0 and make such operation entirely secure as will now be described.

For removing the lid 11, the two pull tabs 22, 23 are grasped with the left and the right hand and are pulled outwardly in the direction of arrows 30 until the crimp zones 19 adjacent the base lines 24 are pulled outwardly and upwardly and are thus disengaged from the flange 12. At the same time there also occurs a partial disengagement of the residual corner zones of the crimp adjoining the base lines 24 of the tabs 22, 23. The latter and the crimp zones adjoining the base lines 24 extend then from the flange 12 of the receptacle 10 generally outwardly as illustrated in dash-dotted line at 31 in FIG. 2. Thereafter the crimp at the comer zones may be entirely disengaged in a simple manner by bending upwardly the two outwardly pulled zones of the lid, for example, into the positions indicated at 32 in FIG. 2. During this operation only those zones of the lid bend upwardly about the crease lines 29 which are disposed at that side thereof which are closer to the respective end of the container. As a result of this operation, the crimp will be entirely disengaged in the corner zones. The buckling of the corresponding ranges of the lid 11 about the crease lines 29 and the complete disengagement of the crimp is particularly securely ensured and made easy by the slits 27. By using a very small force it is now possible to entirely remove the lid 11 in a direction parallel to the opening plane of the receptacle 10 by pulling it in either one or the direction as indicated by the arrow 40. During this sliding motion of the lid 11 the two first straight flange ranges 16, 18 serve as guides (guide rails) for those edge ranges of the lid 11 which are bent thereabout.

What is claimed is:

1. In a two-part thin-walled metal container for storing and serving prepared food, said container being of the type that has a receptacle and a lid removably secured thereto for covering the same, the improvement comprising,

A. a continuous flange forming part of said receptacle and having 1. two straight, opposed, parallel first flange zones which serve as guide rails for guiding the removal of said lid from said receptacle,

2. two opposed second flange zones,

3. rounded corner zones, each connecting a first flange zone with a second flange zone,

B. a continuous edge zone forming part of said lid and bent about said continuous flange to form a continuous crimp and C. a pull tab formed integrally with and as a continuation of each of those portions of the crimped continuous edge zone of said lid that lies beneath said second flange zones of the receptacle flange and having a base portion connected to the part of the crimped continuous edge zone that lies beneath the corner zones flanking its respective second flange zone; upon exerting a manual pulling force on both said pull tabs, the adjacent crimp portion about the associated second flange zone and about the flanking corner zones being disengaged to an extent that said lid being adapted to be slid relative to said first flange zone guide rails and removed from said receptacle. 2. An improvement as defined in claim 1, including two crease lines preformed in the upper side of said lid and extending substantially from one first flange zone t0 the other and being spaced from said second flange 4. An improvement as defined in claim 1, including slits provided in said continuous edge zone at each end of each said first flange zone.

5. An improvement as defined in claim 2, including oppositely aligned pairs of slits provided in said continuous edge zone at each end of each crease line.

6. An improvement as defined in claim 1, wherein at least one of said tabs comprises a plurality of juxtaposed pull tabs.

7. An improvement as defined in claim 1, said lid having a wall thickness of about 0.03 0.08 mm.

8. An improvement as defined in claim 1, wherein the base of each of said tabs extends approximately to the middle of each corner zone flanking the associated second flange zone.

9. An improvement as defined in claim 1, wherein the base of each of said tabs extends substantially beyond the middle of each comer zone flanking the associated second flange zone. 

1. In a two-part thin-walled metal container for storing and serving prepared food, said container being of the type that has a receptacle and a lid removably secured thereto for covering the same, the improvement comprising, A. a continuous flange forming part of said receptacle and having
 1. two straight, opposed, parallel first flange zones which serve as guide rails for guiding the removal of said lid from said receptacle,
 2. two opposed second flange zones,
 3. rounded corner zones, each connecting a first flange zone with a second flange zone, B. a continuous edge zone forming part of said lid and bent about said continuous flange to form a continuous crimp and c. a pull tab formed integrally with and as a continuation of each of those portions of the crimped continuous edge zone of said lid that lies beneath said second flange zones of the receptacle flange and having a base portion connected to the part of the crimped continuous edge zone that lies beneath the corner zones flanking its respective second flange zone; upon exerting a manual pulling force on both said pull tabs, the adjacent crimp portion about the associated second flange zone and about the flanking corner zones being disengaged to an extent that said lid being adapted to be slid relative to said first flange zone guide rails and removed from said receptacle.
 2. two opposed second flange zones,
 2. An improvement as defined in claim 1, including two crease lines preformed in the upper side of said lid and extending substantially from one first flange zone to the other and being spaced from said second flange zones.
 3. An improvement as defined in claim 2, wherein each said crease line is located at a distance from its respective second flange zone that is identical to the radius of curvature of the adjacent corner zone.
 3. rounded corner zones, each connecting a first flange zone with a second flange zone, B. a continuous edge zone forming part of said lid and bent about said continuous flange to form a continuous crimp and c. a pull tab formed integrally with and as a continuation of each of those portions of the crimped continuous edge zone of said lid that lies beneath said second flange zones of the receptacle flange and having a base portion connected to the part of the crimped continuous edge zone that lies beneath the corner zones flanking its respective second flange zone; upon exerting a manual pulling force on both said pull tabs, the adjacent crimp portion about the associated second flange zone and about the flanking corner zones being disengaged to an extent that said lid being adapted to be slid relative to said first flange zone guide rails and removed from said receptacle.
 4. An improvement as defined in claim 1, including slits provided in said continuous edge zone at each end of eacH said first flange zone.
 5. An improvement as defined in claim 2, including oppositely aligned pairs of slits provided in said continuous edge zone at each end of each crease line.
 6. An improvement as defined in claim 1, wherein at least one of said tabs comprises a plurality of juxtaposed pull tabs.
 7. An improvement as defined in claim 1, said lid having a wall thickness of about 0.03 - 0.08 mm.
 8. An improvement as defined in claim 1, wherein the base of each of said tabs extends approximately to the middle of each corner zone flanking the associated second flange zone.
 9. An improvement as defined in claim 1, wherein the base of each of said tabs extends substantially beyond the middle of each corner zone flanking the associated second flange zone. 